My problem is that the control knob that changes the direction of where the air flow is directed does not work. All of the heat or air condioning is directed from the dash vents, so you are constanly being blasted with hot air in your face and your feet freeze! Also in bad weather I have problems keeping the windshield clean because I do not have the full force of the defroster on the windshield. Is this a big job or is it a simple thing to repair I just spent $750.00 on a new fuel pump so I really can not go into a big expense. thank you Michelle F.
Heater Controls on 2000 Chevrolet Blazer
Michelle, from the info I have, it looks like the vents are controlled by a vacuum controller. It's possible that the controller has failed, or there is a vacuum leak. Do you hear a hissing noise from the dash area when the engine is running?